The hydroamination of commodity and specialty alcohols, aldehydes and ketones to manufacture the corresponding aliphatic amines is known in the art. The selection of a catalyst with optimal advantages has also been the focus of much research. Aliphatic amines are of considerable industrial importance and find applications in many facets of modern technology, agriculture and medicine. Lower aliphatic amines (C.sub.1 to C.sub.6) are particularly important for both the chemical and pharmaceutical industries.
In an article titled "Equilibrium Conditions for Amination of Alcohols and Carbonyl Compounds", Ind. Eng. Chem. Prod. Res. Develop., 11, 3, 333-337 (1972), Josef Pasek et al. described the influence of pressure, temperature, and initial composition on the equilibrium content of primary, secondary, and tertiary amines and unsaturated compounds.
Alfons Baiker et al., in an article titled "Catalytic Amination of Long Chain Aliphatic Alcohols", Ind. Eng. Chem., Prod. Res. Dev., 16, 3, 261-266 (1977), indicate a preference for the use of a copper catalyst in the amination of dodecanol with dimethylamine.
In Catalysis of Organic Reactions, Blackburn, D. W., ed., 1990, at Chapter 14, M. Ford et al. review the selective synthesis of mixed alkyl amines by amine-alcohol reactions over hydrogen phosphate.
The amination of alcohols, aldehydes, and ketones using catalysts containing nickel, copper, or both, has been also been described, for example, in U.S. Pat. Nos. 3,520,933; 4,153,581; 4,152,353; and 4,409,399. These patents do not appear to contemplate the selective production of diamines.
The process disclosed in U.S. Pat. No. 4,683,336 employs catalysts comprising carbonates of copper, nickel, and cobalt, or mixtures thereof to produce amines from aliphatic alcohols or aliphatic aldehydes.
U.S. Pat. No. 4,806,690 discloses a method of preparing amines from an alcohol, aldehyde, ketone or mixture thereof, in the presence of a catalyst containing about 1 to 20% cobalt, 75 to 95% copper, 1 to 16% of a third component selected from iron, zinc, zirconium, and mixtures thereof. The preferred embodiment demonstrates the reductive amination of MEA.
U.S. Pat. No. 3,270,059 discloses the production of diaminoalkanes by passing an alkanediol, alkanolamine, alkylene oxide, or alkyleneimine along with either ammonia or an alkylamine in the presence of hydrogen and at an elevated temperature over a catalyst which contains sintered cobalt or nickel. The sintering process requires extra steps and high temperatures.
From the foregoing references it appears there is a need in the art for an improved method of selectively producing shorter chain diaminoalkanes. There does not appear to be a disclosure of the amination a short chain diol, such as, for example, 1,3-propanediol to 1,3-propanediamine in one step with greater than 90% conversions of 1,3-propanediol per pass. It would be very desirable in the art if a process were available for aminating a diol which is available in large volumes. This would provide an attractive route to an added-value commodity chemical. These diamines could find large volume applications in polyamide resins as monomer/comonomers, as well as price-competitive usage in lube oils, epoxies, hot melt adhesives, and surfactants. They might also be useful in fuel additives, chelating agents, fungicides, and plastic lubricants.